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=Acsk4E:N-套5-(:u以一 2 w动ta,41 ≥51-4(3+)=4厂肉+奇 ()-(A-(c国④+刻 (出-:出A And this gets reslly messy when exp anded. the torit thing to note ts thef because of Hwe Quadratic dependence of the interne energy on Eii, the epproxiwete strah enery wiw here terms tht ehe surdreftic in the anknown s. The_poential f the exter ne forces only has linear depadhe on Ss When le dordives 4s ore coot ed we obtain, a war aco lineer systen on he c knowns indri This corresponds i the Qener d 3D poolewe We wil L ws pocedure to specht problems (beens for 过+Fes甲pn
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K2=E(4)+E工22=2Er2 Ka2=Ed=((4=4E工 =×91 R2=2 12 2E1[42,)=2 2L42C CC 0(x)==9X1+8C 94E工 leT